Hemispherx Biopharma Press Release for
Monday, May 05, 2014

……Non-Human Primate Animal Testing Planned as This Deadly New Virus Now Reaches The United States and Southeast Asia, and Disease Incidence Accelerates

Philadelphia, PA, Monday, May 05, 2014: Hemispherx Biopharma (NYSE MKT: HEB) announced that one of its advanced stage biological products, Alferon® N, significantly inhibited the replication of the MERS virus in vitro. MERS-CoV is a recently emerged human coronavirus responsible for the lethal pulmonary syndrome known as MERS (Middle East Respiratory Syndrome). Recent testing in laboratories of the National Institute of Allergy and Infectious Diseases (NIAID), part of the National Institutes of Health, has revealed that Alferon® N was inhibitory to MERS-CoV both when used before test cells were exposed to MERS-CoV, as well as after the cells were exposed to the deadly virus.

Over 400 cases of MERS infection, including over 100 deaths, have been reported to date. More than 200 new cases of MERS infection were seen in the month of April, exceeding the total for the preceding two years since the disease emerged in 2012, according to the Center for Infectious Disease Research and Policy (CIDRAP) on April 30, 2014. Health officials say there is no known cure for MERS, and they have little information about the origins of the virus and how it is transmitted.

NIAID researchers led the Alferon® N MERS-CoV experiments. They treated monkey kidney cells with Alferon® N either 18 hours prior to infection with MERS-CoV (“pre-treatment”) or 1 hour following infection with MERS-CoV (“post-treatment”). At Day 1 and Day 3, supernatants were collected from cells and virus titers were thereafter measured. In both cases, Alferon® N showed significant dose-dependent inhibitory effects, thus suggesting the potential of Alferon® N both as a preventive and a potential treatment. Laboratory (in vitro) studies of potential antiviral agents are not necessarily predictive of clinical benefits. The Company was not involved in the conduct of the experimentation. The results were forwarded to Hemispherx at the conclusion of the experiments and formal publication is pending.

Juergen Richt, DVM, PhD, Regents Distinguished Professor at Kansas State University, stated “This is encouraging news. Non-human primate animal model testing of Alferon may give us more definitive data about the efficacy of this natural interferon against MERS.”

The deadly MERS disease, originally identified in the Middle East, has recently claimed its first victims in Southeast Asia killing a Malaysian man who returned from pilgrimage in Saudi Arabia according to WHO as reported in the WSJ on April 18, 2014. Although this did not happen during the past hajj, infectious disease specialists have been concerned that the illness could spread far afield by the millions of pilgrims who come to the Saudi holy city of Mecca each year for the Muslim pilgrimage. Most of the identified cases have been in Saudi Arabia although increasing numbers are being reported in the Gulf countries. Europe has reported a handful of cases, all with links to the Middle East. The US has just reported its first case of MERS. MERS has been estimated to kill about ¼ (one-fourth) of the people it infects, largely through respiratory infections. The MERS-CoV replicates in camels which may serve as an animal reservoir for the virus. About half of the current cases have involved health workers. Alferon® N has been demonstrated previously to be active against SARS-CoV (Emerging Infectious Disease, Vol. 10, No. 4, April 2004), a closely related human coronavirus responsible for the deadly SARS (Severe Acute Respiratory Syndrome) pandemic. The SARS pandemic that was contained nevertheless resulted in global concern and economic challenges for China, Malaysia, and Canada (http://www.cbc.ca/news/health/mers-virus-outbreak-raising-sars-like-concern-1.2615531).

Hemispherx now plans to expand a comprehensive testing program in collaboration with government researchers.

About Alferon® N Alferon® N is the only natural source, multi-species alpha interferon currently approved for sale in the U.S. Alferon® N is approved in the U.S. only for the treatment of refractory or recurring external genital warts caused by human papilloma virus (“HPV”) in patients 18 years of age or older.

About Hemispherx BiopharmaHemispherx Biopharma, Inc. is an advanced specialty pharmaceutical company engaged in the manufacture and clinical development of new drug entities for treatment of seriously debilitating disorders. Hemispherx’s flagship products include Alferon N Injection® and the experimental therapeutics Ampligen® and Alferon® LDO. Ampligen® is an experimental RNA nucleic acid being developed for globally important debilitating diseases and disorders of the immune system, including Chronic Fatigue Syndrome. Hemispherx’s platform technology includes components for potential treatment of various severely debilitating and life threatening diseases. Because both Ampligen® and Alferon® LDO are experimental in nature, they are not designated safe and effective by a regulatory authority for general use and are legally available only through clinical trials. Hemispherx has patents comprising its core intellectual property estate and a fully commercialized product (Alferon N Injection®), approved for sale in the U.S. and Argentina. The Company’s Alferon® N approval in Argentina includes the use of Alferon N Injection® (under the brand name “Naturaferon”) for use in any patients who fail, or become intolerant to recombinant interferon, including patients with chronic active hepatitis C infection. The Company wholly owns and exclusively operates a GMP certified manufacturing facility in the United States for commercial products. For more information please visit www.hemispherx.net.

Disclosure NoticeInformation contained in this news release, other than historical information, should be considered forward-looking and is subject to various risk factors and uncertainties. For instance, the strategies and operations of Hemispherx involve risk of competition, changing market conditions, changes in laws and regulations affecting these industries and numerous other factors discussed in this release and in the Company’s filings with the Securities and Exchange Commission. The final results of these efforts and/or any other activities could vary materially from Hemispherx’s expectations. In vitro experiments are not necessarily predictive of clinical outcome and no representations are made that any products described in this release will be ultimately determined safe and effective in the prevention and/or treatment of MERS-CoV.

Forward-Looking StatementsTo the extent that statements in this press release are not strictly historical, all such statements are forward-looking, and are made pursuant to the safe harbor provisions of the Private Securities Litigation Reform Act of 1995. Words such as “potential,” “potentially,” “possible,” and similar expressions are intended to identify forward-looking statements. The inclusion of forward-looking statements should not be regarded as a representation by Hemispherx that any of its plans will be achieved. These forward-looking statements are neither promises nor guarantees of future performance, and are subject to a variety of risks and uncertainties, many of which are beyond Hemispherx’s control, which could cause actual results to differ materially from those contemplated in these forward-looking statements. Examples of such risks and uncertainties include those set forth in the Disclosure Notice, above, as well as the risks described in Hemispherx’s filings with the Securities and Exchange Commission, including the most recent reports on Forms 10-K, 10-Q and 8-K. You are cautioned not to place undue reliance on these forward-looking statements, which speak only as of the date hereof, and Hemispherx undertakes no obligation to update or revise the information contained in this press release, whether as a result of new information, future events or circumstances or otherwise revise or update this release to reflect events or circumstances after the date hereof.